在俄语中，名字'Anna'在称呼某人时会变成'Anna'，这展示了呼格形式。

In Russian, the name 'Anna' changes to '___Anna' when addressing someone, showing the ___vocative form.

“孩子们，该吃饭了！”这句话中“孩子们”是呼格用法。

"Kids, it's time for dinner!" uses ___vocative to directly address the children.